package com.eto.etoplayer.util
{
public final class Random{
        
    public function Random(){
            throw new Error("随机函数工具包无法实例化！");
    }
    
    //获取一个随机的布尔值
    public static function get boolean():Boolean{
            return Boolean(integer(2));
    }
    
    //获取一个正负波动值
    public static function get wave():int{
            return integer(2) * 2 - 1;
    }
    
    //获取一个随机的范围整数值
    public static function integer(num:Number):int{
            return Math.floor(number(num));
    }
    
    //获取一个随机的范围Number值
    public static function number(num:Number):Number{
            return Math.random() * num;
    }
    
    //在一个范围内获取一个随机值，返回结果范围：num1 >= num > num2
    public static function range(num1:Number,num2:Number,isInt:Boolean = true):Number{
            var num:Number = number(num2 - num1) + num1;
            if(isInt) num = Math.floor(num);
            return num;
    }
    
    //在多个范围获取随机值
    public static function ranges(...args):Number{
            var isInt:Boolean = args[args.length - 1] is Boolean ? args.pop() : true;
            var num:Number = randomRange(args);
            if(!isInt) num += Math.random();
            return num;
    }
    
    //获取一个随机字符，默认随机范围为数字+大小写字母，也可以指定范围，格式：a-z,A-H,5-9
    public static function string(str:String = "0-9,A-Z,a-z"):String{
            return String.fromCharCode(randomRange(explain(str)));
    }
    
    //生成指定位数的随机字符串
    public static function bit(num:int,str:String = "0-9,A-Z,a-z"):String{
            var reStr:String = "";
            for(var i:int = 0; i < num; i ++) reStr += string(str);
            return reStr;
    }
    
    //获取一个随机的颜色值
    public static function color(red:String = "0-255",green:String = "0-255",blue:String = "0-255"):uint{
            return Number("0x" + transform(randomRange(explain(red,false))) +
                                                     transform(randomRange(explain(green,false))) +
                                                     transform(randomRange(explain(blue,false))));
    }
    
    //将10进制的RGB色转换为2位的16进制
    private static function transform(num:uint):String{
            var reStr:String = num.toString(16);
            if(reStr.length != 2) reStr = "0" + reStr;
            return reStr;
    }
    
    //字符串解析
    private static function explain(str:String,isCodeAt:Boolean = true):Array{
            var argAr:Array = new Array;
            var tmpAr:Array = str.split(",");
            for(var i:int = 0; i < tmpAr.length; i ++){
                    var ar:Array = tmpAr[i].split("-");
                    if(ar.length == 2){
                            var arPush0:String = ar[0];
                            var arPush1:String = ar[1];
                            if(isCodeAt){
                                    arPush0 = arPush0.charCodeAt().toString();
                                    arPush1 = arPush1.charCodeAt().toString();
                            }
                            //此处如果不加1，将不会随机ar[1]所表示字符，因此需要加上1，随机范围才是对的
                            argAr.push(Number(arPush0),Number(arPush1) + 1);
                    }else if(ar.length == 1){
                            var arPush:String = ar[0];
                            if(isCodeAt) arPush = arPush.charCodeAt().toString();
                            //如果范围是1-2，那么整型随机必定是1，因此拿出第一个参数后，把范围定在参数+1，则就是让该参数参加随机
                            argAr.push(Number(arPush),Number(arPush) + 1);
                    }
                    ar = null;
            }
            tmpAr = null;
            return argAr;
    }
    
    //获取随机范围
    private static function randomRange(ar:Array):Number{
            var tmpAr:Array = new Array;
            var length:int = ar.length;
            if(length % 2 != 0 || length == 0) throw new Error("参数错误！无法获取指定范围！");
            //将所有可能出现的随机数存入数组，然后进行随机
            for(var i:int = 0; i < length / 2; i ++){
                    var i1:int = ar[i * 2];
                    var i2:int = ar[i * 2 + 1];
                    if(i1 > i2){
                            var tmp:Number = i1;
                            i1 = i2;
                            i2 = tmp;
                    }
                    for(i1; i1 < i2; i1 ++) tmpAr.push(i1);
            }
            var num:Number = tmpAr[integer(tmpAr.length)];
            tmpAr = null;
            ar = null;
            return num;
    }
        
}
}